QTemporaryFile tf;
tf.open ();
QDataStream tfbs (&tf);
tfbs << "hello\r\n" << "world!\r\n";
const int pos = int (tf.pos ());
QByteArray ba;
ba.append ("hello\r\n");
ba.append ("world!\r\n");
const int size = ba.size ();
Basically my question is, what am I doing wrong? Why is pos > size? Should I not be using << ? Should I not be using QDataStream?
Edit: Is there a way to configure QDataStream or QTemporaryFile so that the << operator doesn't prepend strings with 32bit lengths and store the null terminators in the file? Calling QDataStream::writeBytes when I just have a series of quoted strings and QStrings makes for very ugly code.
The answer is in the docs. I'm not going to go over QByteArray, as I believe it's fairly obvious that it is working as expected.
The QDataStream operator<<(char*) overload evaluates to the writeBytes() function.
This function outputs:
Writes the length specifier len and the buffer s to the stream and returns a reference to the stream. The len is serialized as a quint32, followed by len bytes from s. Note that the data is not encoded.
So for "hello\r\n", I would expect the output to be:
0,0,0,8,'h','e','l','l','o','\r','\n',0
The 4-byte length, followed by the bytes from the string. The string-ending NULL is probably also being added to the end, which would account for the otherwise mysterious extra two bytes.